Since commercial deployment of fourth generation (4G) communication systems, to meet the ever increasing demand for wireless data traffic, efforts have been made to develop improved fifth generation (5G) or pre-5G communication systems. As such, 5G or pre-5G communication systems are also called “beyond 4G network” or “post long-term evolution (LTE) system”. To achieve higher data rates, 5G communication systems consider utilization of the millimeter wave (mmWave) band (e.g., 60 GHz band). To decrease path loss and increase the transmission distance in the mmWave band, various technologies including beamforming, massive multiple-input multiple-output (massive MIMO), full dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large scale antennas are considered for 5G communication systems. To improve system networks in 5G communication systems, technology development is under way regarding evolved small cells, advanced small cells, cloud radio access networks (cloud RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving networks, cooperative communication, coordinated multi-points (CoMP), reception interference cancellation, and the like. In addition, advanced coding and modulation (ACM) schemes, such as hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC), and advanced access technologies, such as filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) are also under development for 5G communication systems.
Meanwhile, the Internet is evolving from a human centered network where humans create and consume information into the Internet of Things (IoT) where distributed elements or things process and exchange information. There has also emerged the Internet of Everything (IoE) technology that combines IoT technology with big data processing technology through connection with cloud servers. To realize IoT services, base technologies, such as sensing, wired/wireless communication and network infrastructure, service interfacing and security are needed, and technologies interconnecting things, such as sensor networks, machine-to-machine (M2M) or machine type communication (MTC) are under development. In IoT environments, it is possible to provide intelligent Internet technology services, which collect and analyze data created by interconnected things to add new values to human life. Through convergence and combination between existing information technologies and various field technologies, IoT technology may be applied to various areas, such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, health-care, smart consumer electronics, and advanced medical services.
Accordingly, various attempts are being made to apply 5G communication systems to IoT networks. For example, sensor networks and M2M or MTC are being realized by use of 5G communication technologies including beamforming, MIMO and array antennas. Application of cloud RANs to big data processing described above may be an instance of convergence of 5G communication technology and IoT technology.
A reference signal (RS) is a signal that is used to measure the state of the channel between the base station (BS) and users, such as channel strength, distortion, interference strength and Gaussian noise, in a wireless mobile communication system and is also used to assist in demodulation and decoding of received data symbols. One of the primary uses of the (RS) is to measure the radio channel state. The receiver can determine the state of the radio channel between itself and the transmitter by measuring the received strength of a (RS) that has been transmitted by the transmitter at a given transmission power and has passed through the radio channel. The state of the radio channel is used to determine the data rate the receiver will request to the transmitter.
In the LTE system, the terminal performs data channel decoding and channel estimation by using the demodulation reference signal (DMRS) among various reference signals.
Therefore, a need exists for a method in the 5G system for improving channel estimation performance using the DMRS.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.